dlist 0.3.1 → 0.3.2

raw patch · 3 files changed

+44/−13 lines, 3 filesPVP: major bump suggested

API removals or changes: PVP suggests a major version bump

API changes (from Hackage documentation)

Files

• Data/DList.hs +31/−8
• dlist.cabal +11/−5
• tests/Properties.hs +2/−0

@@ -14,7 +14,7 @@  module Data.DList ( -  DList         -- abstract, instance Monoid, Functor, Monad, MonadPlus+   DList(..)         -- abstract, instance Monoid, Functor, Applicative, Monad, MonadPlus    -- * Construction   ,fromList      -- :: [a] -> DList a@@ -40,15 +40,32 @@   ) where  import Prelude hiding (concat, foldr, map, head, tail)+import qualified Data.List as List import Control.Monad-import qualified Data.List as List (concat, foldr, map, unfoldr)+import Control.Applicative(Applicative(..)) import Data.Monoid  -- | A difference list is a function that given a list, returns the -- original contents of the difference list prepended at the given list ----- This structure supports /O(1)/ append and snoc operations on lists.+-- This structure supports /O(1)/ append and snoc operations on lists,+-- making it very useful for append-heavy uses, such as logging and+-- pretty printing. --+-- For example, using DList as the state type when printing a tree with+-- the Writer monad+--+-- > import Control.Monad.Writer+-- > import Data.DList+-- > +-- > data Tree a = Leaf a | Branch (Tree a) (Tree a)+-- >+-- > flatten_writer :: Tree x -> DList x+-- > flatten_writer = snd . runWriter . flatten+-- >     where+-- >       flatten (Leaf x)     = tell (singleton x)+-- >       flatten (Branch x y) = flatten x >> flatten y+-- newtype DList a = DL { unDL :: [a] -> [a] }  -- | Converting a normal list to a dlist@@ -95,10 +112,10 @@  -- | /O(length dl)/, List elimination, head, tail.  list :: b -> (a -> DList a -> b) -> DList a -> b-list null cons dl =+list nill consit dl =   case toList dl of-    [] -> null-    (x : xs) -> cons x (fromList xs)+    [] -> nill+    (x : xs) -> consit x (fromList xs)  -- | Return the head of the list head :: DList a -> a@@ -113,7 +130,7 @@ unfoldr pf b =   case pf b of     Nothing     -> empty-    Just (a, b) -> cons a (unfoldr pf b)+    Just (a, b') -> cons a (unfoldr pf b')  -- | Foldr over difference lists foldr        :: (a -> b -> b) -> b -> DList a -> b@@ -133,6 +150,12 @@     fmap = map     {-# INLINE fmap #-} +#if __GLASGOW_HASKELL__ >= 608+instance Applicative DList where+    pure  = return+    (<*>) = ap+#endif+ instance Monad DList where   m >>= k     -- = concat (toList (fmap k m))@@ -146,7 +169,7 @@   return x = singleton x   {-# INLINE return #-} -  fail s   = empty+  fail _   = empty   {-# INLINE fail #-}  instance MonadPlus DList where

@@ -1,14 +1,20 @@ Name:                dlist-Version:             0.3.1+Version:             0.3.2 Synopsis:            Differences lists-Description:         Differences lists: a list-like type supporting O(1) append+Description:         +    Differences lists: a list-like type supporting O(1) append.+    This is particularly useful for efficient logging and pretty+    printing, (e.g. with the Writer monad), where list append +    quickly becomes too expensive. Category:            Data License:             BSD3 License-file:        LICENSE Author:              Don Stewart -Maintainer:          dons@cse.unsw.edu.au+Maintainer:          dons@galois.com+Copyright:           2006-7 Don Stewart+Homepage:            http://www.cse.unsw.edu.au/~dons/dlist.html Build-Depends:       base-Ghc-options:         -O2+Ghc-options:         -O2 -Wall+Extensions:          CPP Exposed-modules:     Data.DList-Homepage:            http://www.cse.unsw.edu.au/~dons/dlist.html extra-source-files:  README tests/Properties.hs tests/Parallel.hs

@@ -72,7 +72,9 @@ -- missing QC instances -- +{- instance Arbitrary a => Arbitrary (Maybe a) where   arbitrary           = do a <- arbitrary ; elements [Nothing, Just a]   coarbitrary Nothing = variant 0   coarbitrary _       = variant 1 -- ok?+      -}